U.S. Pat. No. 6,644,592 to Parrott, et al. (the “Parrott '592 patent”) provides an example of a type of helicopter flotation system currently available for use. The system includes a C-shaped girt attached directly to a horizontal landing skid of a helicopter. Packed within a flexible cover are multiple “side” and “center” floats which may be inflated upon deployment. Also included within the cover is an inflatable life raft.
As detailed in the Parrott '592 patent, prior to deployment the deflated floats are packed around the deflated raft within the cover. Hence, only upon inflation of the floats do the floats and raft separate in any way. Indeed, inflation of the floats is a prerequisite to exposure of the raft, as such inflation both disengages fasteners associated with the cover (and end caps) and displaces the floats from the raft, thereby allowing for inflation of the raft as well. See, e.g., Parrott '592 patent, col. 3, 11. 9-51; FIG. 1.
Disclosed in U.S. Pat. No. 6,709,305 to Parrott, et al. (the “Parrott '305 patent”) is a similar flotation system. Confirmed in the Parrott '305 patent is the deployment sequence of the floats and life raft. When a helicopter must land on water, the system initially is “partially deployed,” with the floats being completely inflated “while the raft remains packed.” See Parrott '305, col. 3, 1. 66 through col. 4, 1. 2. Such partial deployment occurs using a first switch, which releases gas from a canister into an air hose and thence to the floats. See id., col. 4, 11. 9-12. Following complete inflation of the floats, a second switch may be employed to inflate the raft. See id., 11. 30-35.
Absent from the Parrott '592 and '305 patents is any discussion of floats and rafts packed independently and not directly attached to any portion of a helicopter. Similarly omitted from these patents is recognition that a life raft need not always be included as part of the flotation system and that maintenance of the floats and raft need not always occur simultaneously. Moreover, situations in which utilizing only a single switch or other actuator for both the floats and raft likewise are not contemplated by the Parrott '592 and '305 patents.